Are conkers harm full to field mice?

Yes, conkers, or horse chestnuts, can be harmful to field mice and other animals if consumed. They contain compounds called saponins and alkaloids, which can cause gastrointestinal distress and other health issues. While field mice may nibble on them, it's best for them to avoid conkers to prevent potential toxicity. Overall, while not commonly lethal, conkers are not a suitable food source for field mice.